Panel transportation device

ABSTRACT

A panel transportation device of the present invention has a panel grasp portion for grasping a panel, a link mechanism for moving the panel grasp portion in a panel transportation direction, and a slide mechanism for operating the link mechanism so as to move the panel grasp portion in the panel transportation direction and moving the entire link mechanism. The slide mechanism is constituted of a first slide mechanism with a first slide block and a second slide mechanism with a second slide block. The link mechanism is constructed such that the first slide block and the second slide block are connected to the panel grasp portion and the panel grasp portion is moved in the panel transportation direction by individually and linearly driving the first slide block and the second slide block.

This is a National Phase Application in the United States ofInternational Patent Application No. PCT/JP2004/006748 filed May 19,2004, which claims priority on Japanese Patent Application No.142399/2003, filed May 20, 2003, Japanese Patent Application No.045975/2004, filed Feb. 23, 2004, and Japanese Patent Application No.045928/2004, filed Feb. 23, 2004. The entire disclosures of the abovepatent applications are hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a panel transportation device whichtransports a panel molded by a press or the like.

BACKGROUND ART

For example, a panel for an automobile has a complicated shape, so thata mold process is divided into several steps, and the panel is molded bylinearly arranged molds. In a transfer press or tandem press using sucha plurality of presses, a panel transportation device is provided tosequentially transport members (panels) molded in a certain press to asubsequent press.

A crossbar type transportation device in Patent document 1 below hasheretofore been widely used as the panel transportation device for thetransfer press. In this device, a lift beam extending throughout pressstations is provided so as to be able to ascend and descend in a linedirection; a carrier is further suspended from the lift beam so as to beable to reciprocate among the respective stations in the line direction;a crossbar is set to the carrier; and a work grasp portion is attachedto the crossbar, whereby work materials of the respective stations aresimultaneously and intermittently transported.

Such a crossbar type transportation device has the followingcharacteristics.

(1) Feed motion of a molded panel among mold stations is generated undermotion control by cam driving or by an AC servo motor.

(2) The panel is transported by composite motion in a feed direction(horizontal direction) and a lift direction (vertical direction), and avacuum cup attached to a transportation tool called the crossbar sucksand transports the panel.

(3) The crossbars among the mold stations are coupled both in the feeddirection and the lift direction, and the respective crossbars areinterlocked with each other and make totally the same motion.

(4) A feed arm which generates the feed motion among the stations isgenerally located on a front or rear side of a series of feed devicesgenerally constituted of a carriage connecting the crossbars and of alink mechanism thereof, and the feed motion is generated by swinging thearm.

Furthermore, in addition to the crossbar type transportation devicedescribed above, there have been proposed panel transportation devicesdescribed in Patent documents 2 to 3 and the like below.

In a “transfer feeder” described in Patent document 2, a pair of liftbeams moved up and down by a lifter is provided with a plurality ofcarriers which are independently self-propelled by a linear motor, andthe linear motor is used as a drive source to enable high-speedtransportation of a work (panel).

In a “transfer press transportation device” as is described in Patentdocument 1, a plurality of carriers is provided in a lift beam, and aservo motor is used as a drive source for the carriers to enablehigh-speed transportation of a work (panel).

A transport and positioning system described in Patent document 3comprises a driver 40 having a lever mechanism 33 with an output portion35 which drives and positions a crossbar 32, as shown in FIG. 1. Thislever mechanism 33 has a swing arm 34 forming the output portion 35 atone end, and the output portion 35 is coupled to the crossbar 32.Further, the swing arm 34 is coupled at two points: a support point 38and a drive point 43 distanced from each other. The distance between thesupport point 38 and the drive point 43 is shorter than a distancebetween the output portion and the support point. It is to be noted thatin FIG. 1, 31 denotes a work grasp portion attached to the crossbar 32;42 denotes a guide rod coupling a slide block 47 with the drive point43; 51 denotes a swing motor which swings the guide rod 42; and 55denotes a direct acting device which moves the slide block 47 up anddown.

In this configuration, the slide block 47 is moved up and down by thedirect acting device 55, and the swing motor 51 swings the guide rod 42to drive/position a tip (the drive point 43) of the guide rod 42, andthen this motion is enlarged by a leverage ratio to drive/position thecrossbar 32 to which the work grasp portion 31 is attached.

Patent document 1: Japanese Patent Publication Laid-open No. 10-328766

Patent document 2: Japanese Examined patent publication No. 7-73756

Patent document 3: U.S. Pat. No. 6,382,400

However, the panel transportation devices described in Patent document 1described above have the following problems: (1) the respectivecrossbars cannot have motions different from each other; (2) the servomotor and a feed driver are increased in size since the crossbars forall the stations are simultaneously moved; and (3) since motion curvesfor the respective press stations are the same, a mold shape needs to bespecially designed to avoid interference, which causes difficulty inaccommodating diversification of plate molding. Further, in a linearmotor method of Patent document 2, high-speed feeding can be achieved bythe linear motor, but a lift mechanism is additionally needed, and thismethod therefore has a problem that an entire structure is complicatedand large. An AC serve method of Patent document 1 has a problem thathigh rigidity cannot be obtained due to a serial link.

Furthermore, in a swing arm method of Patent document 3, since the panelis transported by the swing arm, a longer transportation distancerequires more length of the arm, and, for example, deflection of the armcauses vibration. Moreover, because the panel transportation device inPatent document 3 comprises a slide mechanism vertically driven amongthe press stations, this device cannot be applied to the multislide typetransfer press without an upright for installation of the slidemechanism. Further, in order to correspond to complicated press molding,a tilting device needs to be separately provided in the crossbar to tiltthe work grasp portion, and there is thus a problem that the structureis complicated and weight of movable portions is increased to make itmore difficult to achieve a high speed.

DISCLOSURE OF THE INVENTION

The present invention has been made to solve the foregoing problems.That is, it is a main object of the present invention to provide a paneltransportation device wherein different motion can be made for eachpress station; movable portions can be easily reduced in weight;rigidity of the movable portions can be increased to restrain deflectionand vibration; and the panel transportation device can also be appliedto a multislide type transfer press. It is another object of the presentinvention to provide a panel transportation device in which a work graspportion can be tilted without adding another device to the movableportions while the movable portions are reduced in weight.

In order to attain the object of the present invention, according to afirst invention, there is provided a panel transportation devicecharacterized by comprising: a panel grasp portion for grasping a panel;a link mechanism for moving the panel grasp portion in a paneltransportation direction; and a slide mechanism for operating the linkmechanism so as to move the panel grasp portion in the paneltransportation direction and moving the entire link mechanism.

According to the first invention, the slide mechanism can operate thelink mechanism and move the entire link mechanism to move the panelgrasp portion in the panel transportation direction. Thus, the panelgrasped by the panel grasp portion can be transported in a predeterminedtransportation direction. Further, since the panel transportation deviceof the present invention can be provided for each press station, eachpanel transportation device can have different motion for each pressstation. Still further, because the device itself can be compactlyconfigured, it can also be applied to a multislide type press device.

A second invention is a preferred embodiment of the first invention,wherein a pair of link mechanisms and a pair of slide mechanisms areprovided symmetrically to each other on both sides of the panel graspportion.

According to the second invention, the panel can be stably transported.

A third invention is a preferred embodiment of the first invention,wherein the slide mechanism is constituted of a first slide mechanismand a second slide mechanism provided closer to a transportation linedownstream side than the first slide mechanism. The first slidemechanism has a first slide block connected to the link mechanism, andis configured to linearly drive the first slide block in a directioninclined with respect to a horizontal plane so that the first slideblock is at a high position on a transportation line upstream side andat a low position on the transportation line downstream side within adriving region of the first slide block. The second slide mechanism hasa second slide block connected to the link mechanism, and is configuredto linearly drive the second slide block in a direction inclined withrespect to the horizontal plane so that the second slide block is at alow position on the transportation line upstream side and at a highposition on the transportation line downstream side within a drivingregion of the second slide block. The link mechanism is constructed suchthat the first slide block and the second slide block are connected tothe panel grasp portion and the panel grasp portion is moved in thepanel transportation direction by individually and linearly driving thefirst slide block and the second slide block.

According to the third invention, by directly driving the first slideblock and the second slide block moving in the V-shaped driving region,the panel grasp portion connected to these slide blocks via the linkmechanism can be moved in the panel transportation direction. Thus, thepanel grasped by the panel grasp portion can be transported in thepredetermined transportation direction.

A fourth invention is a preferred embodiment of the third invention,wherein the link mechanism comprises an output member connected to thepanel grasp portion; a first link whose one end is pivotally connectedto the output member and whose other end is pivotally connected to thefirst slide block; and a second link whose one end is pivotallyconnected to the output member and whose other end is pivotallyconnected to the second slide block.

According to the fourth invention, the first slide block is driven tomove the first link and the second slide block is driven to move thesecond link so that the link mechanism is moved, thereby making itpossible to move the panel grasp portion connected to the output memberin the predetermined transportation direction.

A fifth invention is a preferred embodiment of the fourth invention,wherein the first link comprises two arms, and each of the two arms hasone end pivotally connected to the output member and the other endpivotally connected to the first slide block.

According to the fifth invention, the output member can be held in aconstant posture via the two arms, and a work grasp portion attached tothe output member is held in a constant posture, thereby enabling stablepanel transportation.

A sixth invention is a preferred embodiment of the fifth invention,wherein the first slide block is constituted of two slide blocks. Thefirst slide mechanism comprises two driving means for individuallydriving the two slide blocks. The other ends of the two arms arepivotally connected to the two slide blocks. Relative positions of thetwo slide blocks are changed to tilt the panel grasp portion connectedto the output member.

According to the sixth invention, since the panel grasp portion can betilted, the panel can be grasped/mounted at an optimum angle asrequired.

A seventh invention is a preferred embodiment of the fifth invention,wherein a straight line passing pivotal connection points of the twoarms and the first slide block and/or a straight line passing pivotalconnection points of the two arms and the output member is/are inclinedwith respect to the horizontal plane so that it is possible to alwayshold a state where the two arms do not interfere with each other in afigure viewed from a transportation line width direction.

According to the seventh invention, since the straight line passing thepivotal connection points of the two arms and the first slide blockand/or the straight line passing the pivotal connection points of thetwo arms and the output member is/are inclined with respect to thehorizontal plane so that it is possible to always hold the state wherethe two arms do not interfere with each other in the figure viewed fromthe transportation line width direction, the first link alwaysconstructs a quadrilateral link, and a mechanical dead point of the linkmechanism can be eliminated in any position of a panel transportationoperation. It is thereby possible to obtain an advantage thatcontrollability can be significantly improved.

An eighth invention is a preferred embodiment of the sixth invention,wherein a straight line passing pivotal connection points of the twoarms and the first slide block and/or a straight line passing pivotalconnection points of the two arms and the output member is/are inclinedwith respect to the horizontal plane so that it is possible to alwayshold a state where the two arms do not interfere with each other in afigure viewed from a transportation line width direction.

According to the eighth invention, since the straight line passing thepivotal connection points of the two arms and the first slide blockand/or the straight line passing the pivotal connection points of thetwo arms and the output member is/are inclined with respect to thehorizontal plane so that it is possible to always hold the state wherethe two arms do not interfere with each other in the figure viewed fromthe transportation line width direction, the first link alwaysconstructs a quadrilateral link, and a mechanical dead point of the linkmechanism can be eliminated in any position of a panel transportationoperation. It is thereby possible to obtain an advantage thatcontrollability can be significantly improved.

A ninth invention is a preferred embodiment of the fourth invention,wherein the second link comprises two arms, and each of the two arms hasone end pivotally connected to the output member and the other endpivotally connected to the second slide block.

According to the ninth invention, the output member can be held in aconstant posture via the two arms, and the work grasp portion connectedto the output member is held in a constant posture, thereby enablingstable panel transportation.

A tenth invention is a preferred embodiment of the ninth invention,wherein the second slide block is constituted of two slide blocks. Thesecond slide mechanism comprises two driving means for individuallydriving the two slide blocks. The other ends of the two arms arepivotally connected to the two slide blocks. Relative positions of thetwo slide blocks are changed to tilt the panel grasp portion connectedto the output member.

According to the tenth invention, since the panel grasp portion can betilted, the panel can be grasped/mounted at an optimum angle asrequired.

An eleventh invention is a preferred embodiment of the ninth invention,wherein a straight line passing pivotal connection points of the twoarms and the second slide block and/or a straight line passing pivotalconnection points of the two arms and the output member is/are inclinedwith respect to the horizontal plane so that it is possible to alwayshold a state where the two arms do not interfere with each other in afigure viewed from a transportation line width direction.

According to the eleventh invention, since the straight line passing thepivotal connection points of the two arms and the second slide blockand/or the straight line passing the pivotal connection points of thetwo arms and the output member is/are inclined with respect to thehorizontal plane so that it is possible to always hold the state wherethe two arms do not interfere with each other in the figure viewed fromthe transportation line width direction, the second link always forms aquadrilateral link, and mechanical dead point of the link mechanism canbe eliminated in any position of a panel transportation operation. It isthereby possible to obtain an advantage that controllability can besignificantly improved.

A twelfth invention is a preferred embodiment of the tenth invention,wherein a straight line passing pivotal connection points of the twoarms and the second slide block and/or a straight line passing pivotalconnection points of the two arms and the output member is/are inclinedwith respect to the horizontal plane so that it is possible to alwayshold a state where the two arms do not interfere with each other in afigure viewed from a transportation line width direction.

According to the twelfth invention, since the straight line passing thepivotal connection points of the two arms and the second slide blockand/or the straight line passing the pivotal connection points of thetwo arms and the output member is/are inclined with respect to thehorizontal plane so that it is possible to always hold the state wherethe two arms do not interfere with each other in the figure viewed fromthe transportation line width direction, the second link always forms aquadrilateral link, and a mechanical dead point of the link mechanismcan be eliminated in any position of a panel transportation operation.It is thereby possible to obtain an advantage that controllability canbe significantly improved.

A thirteenth invention is a preferred embodiment of the third invention,wherein the panel transportation device comprises a tilt mechanism fortilting the panel grasp portion, and the tilt mechanism comprises arotary actuator installed in the first slide block or the second slideblock, and a transmission mechanism for transmitting rotary driving ofthe rotary actuator to tilt the panel grasp portion.

According to the thirteenth invention, since the panel grasp portion canbe tilted by the tilt mechanism, the panel can be grasped/mounted at anoptimum angle as required. Further, since the tilt mechanism comprisesthe rotary actuator installed in the slide block and the transmissionmechanism, the mechanism can be constructed in a simple manner. Stillfurther, since the tilt mechanism and the link mechanism are separatelyconfigured, the mechanical dead point of the link mechanism can beeliminated. Thus, the controllability is significantly improved.

A fourteenth invention is a preferred embodiment of the thirteenthinvention, wherein the transmission mechanism comprises a first armwhose one end is fixed to a drive shaft of the rotary actuator, a secondarm whose one end is fixed to or integrally formed in the output memberor the panel grasp portion, and a coupling rod whose one end ispivotally connected to the other end of the first arm and whose otherend is pivotally connected to the other end of the second arm and whichcouples the first arm with the second arm.

According to the fourteenth invention, the rotary driving of the rotaryactuator is transmitted to the panel grasp portion via the first arm,the coupling rod and the second arm, so that the panel grasp portion canbe tilted. The first link or the second link and the coupling rod havethe same length, and the first arm and the second arm have the samelength. Consequently, they maintain a parallelogram, so that duringnormal transportation without tilt operation, the panel grasp portioncan be always maintained in a constant posture without driving therotary actuator.

A fifteenth invention is a preferred embodiment of the thirteenthinvention, wherein the transmission mechanism comprises a first pulleyfixed to the drive shaft of the rotary actuator, a second pulley fixedto or integrally formed in the output member or the panel grasp portion,and a drive belt for transmitting rotary driving of the first pulley tothe second pulley.

According to the fifteenth invention, the rotary driving of the rotaryactuator is transmitted to the panel grasp portion via the first pulley,the drive belt and the second pulley, so that the panel grasp portioncan be tilted. Furthermore, a ratio of nominal diameter of the firstpulley to that of the second pulley is 1 to 1, so that during normaltransportation without tilt operation, the panel grasp portion can bealways maintained in a constant posture without driving the rotaryactuator.

A sixteenth invention is a preferred embodiment of the third invention,wherein the first slide mechanism and the second slide mechanismcomprise direct acting actuators which linearly drive the first slideblock and the second slide block.

According to the sixteenth invention, the first slide and the secondslide are driven by the direct acting actuators to allow an operation tobe directly transmitted to the link mechanism.

A seventeenth invention is a preferred embodiment of the sixteenthinvention, wherein the direct acting actuator is a ball screw with aball nut, a timing belt, a hydraulic cylinder, a rack and pinion, or alinear motor.

According to the seventeenth invention, the slides can be linearly movedat a high speed and accurately positioned by using the direct actingactuators.

An eighteenth invention is a preferred embodiment of the seventeenthinvention, wherein the panel grasp portion comprises a crossbarconnected to the link mechanism, and a work grasp portion attached tothe crossbar.

According to the eighteenth invention, the crossbar is moved by the linkmechanism, so that the work grasp portion attached to the crossbar canmake a predetermined movement.

Other objects and advantageous features of the present invention will beapparent from a description below with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a panel transportation device according to aprior art;

FIG. 2 is a perspective view showing a first embodiment of the presentinvention;

FIG. 3 is a configuration diagram showing the first embodiment of thepresent invention;

FIG. 4 is a schematic diagram showing the first embodiment of thepresent invention;

FIG. 5A is a diagram explaining a panel transportation operation of thepanel transportation device according to the first embodiment of thepresent invention;

FIG. 5B is a diagram explaining the panel transportation operation ofthe panel transportation device according to the first embodiment of thepresent invention;

FIG. 5C is a diagram explaining the panel transportation operation ofthe panel transportation device according to the first embodiment of thepresent invention;

FIG. 5D is a diagram explaining the panel transportation operation ofthe panel transportation device according to the first embodiment of thepresent invention;

FIG. 5E is a diagram explaining the panel transportation operation ofthe panel transportation device according to the first embodiment of thepresent invention;

FIG. 5F is a diagram explaining the panel transportation operation ofthe panel transportation device according to the first embodiment of thepresent invention;

FIG. 5G is a diagram explaining the panel transportation operation ofthe panel transportation device according to the first embodiment of thepresent invention;

FIG. 6 is a diagram showing motion curves of the panel transportationdevice according to the first embodiment of the present invention;

FIG. 7 is a configuration diagram showing a second embodiment of thepresent invention;

FIG. 8 is a schematic diagram showing the second embodiment of thepresent invention;

FIG. 9A is a diagram explaining a tilt operation of the paneltransportation device according to the second embodiment of the presentinvention;

FIG. 9B is a diagram explaining the tilt operation of the paneltransportation device according to the second embodiment of the presentinvention;

FIG. 9C is a diagram explaining the tilt operation of the paneltransportation device according to the second embodiment of the presentinvention;

FIG. 10A is a diagram explaining a panel transportation operation of thepanel transportation device according to the second embodiment of thepresent invention;

FIG. 10B is a diagram explaining the panel transportation operation ofthe panel transportation device according to the second embodiment ofthe present invention;

FIG. 10C is a diagram explaining the panel transportation operation ofthe panel transportation device according to the second embodiment ofthe present invention;

FIG. 11 is a configuration diagram showing a third embodiment of thepresent invention;

FIG. 12 is a schematic diagram showing the third embodiment of thepresent invention;

FIG. 13 is a diagram wherein a crossbar is moved to a panel mountingposition in the panel transportation device according to the firstembodiment of the present invention;

FIG. 14 is a diagram wherein the crossbar is moved to the panel mountingposition in the panel transportation device according to the thirdembodiment of the present invention;

FIG. 15 is a configuration diagram showing a fourth embodiment of thepresent invention;

FIG. 16 is a schematic diagram showing the fourth embodiment of thepresent invention;

FIG. 17 is a diagram wherein the crossbar is moved to the panel mountingposition in the panel transportation device according to the secondembodiment of the present invention;

FIG. 18 is a configuration diagram showing a fifth embodiment of thepresent invention;

FIG. 19 is a schematic diagram showing the fifth embodiment of thepresent invention;

FIG. 20A is a diagram explaining a panel transportation operation of thepanel transportation device according to the fifth embodiment of thepresent invention;

FIG. 20B is a diagram explaining the panel transportation operation ofthe panel transportation device according to the fifth embodiment of thepresent invention;

FIG. 20C is a diagram explaining the panel transportation operation ofthe panel transportation device according to the fifth embodiment of thepresent invention;

FIG. 20D is a diagram explaining the panel transportation operation ofthe panel transportation device according to the fifth embodiment of thepresent invention;

FIG. 20E is a diagram explaining the panel transportation operation ofthe panel transportation device according to the fifth embodiment of thepresent invention;

FIG. 20F is a diagram explaining the panel transportation operation ofthe panel transportation device according to the fifth embodiment of thepresent invention;

FIG. 20G is a diagram explaining the panel transportation operation ofthe panel transportation device according to the fifth embodiment of thepresent invention;

FIG. 21A is a diagram explaining a tilt operation of the paneltransportation device according to the fifth embodiment of the presentinvention;

FIG. 21B is a diagram explaining the tilt operation of the paneltransportation device according to the fifth embodiment of the presentinvention;

FIG. 21C is a diagram explaining the tilt operation of the paneltransportation device according to the fifth embodiment of the presentinvention;

FIG. 22 is a configuration diagram showing a sixth embodiment of thepresent invention; and

FIG. 23 is a schematic diagram showing the sixth embodiment of thepresent invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the present invention will hereinafter bedescribed in detail with reference to the accompanying drawings. It isto be noted that the same numerals are assigned to common partsthroughout the drawings and redundant explanation is omitted.

FIGS. 2 and 3 are diagrams showing a panel transportation deviceaccording to a first embodiment of the present invention. FIG. 2 is aperspective view showing a panel transportation device 10, and FIG. 3 isa configuration diagram showing a figure of the panel transportationdevice 10 of FIG. 2 from the inside of a transportation line widthdirection. In this drawing, there are shown, for convenience ofexplanation, two press stations 14 on an upstream side and a downstreamside, and the panel transportation device 10 of the present inventionprovided between these press stations. In actual equipment, about two tofive press stations are generally provided. It is to be noted that inthe present description, the “upstream side” and the “downstream side”mean an upstream side and a downstream side of a transportation line,respectively.

As shown in FIGS. 2 and 3, the panel transportation device 10 isdisposed between the press stations 14, 14 to receive a molded material(panel) from the upstream press station 14 and transport it to thedownstream press station 14. Moreover, the panel transportation device10 is disposed between the press stations 14, 14 by attaching its bothends to the upstream and downstream press stations 14 or to armsprovided in an unshown press stand, or by suspending the paneltransportation device 10 from a ceiling.

The panel transportation device 10 comprises a panel grasp portion 15; apair of link mechanisms 6 connected symmetrically to each other on bothsides of the panel grasp portion 15; and slide mechanisms 13 which causethe link mechanisms 6 to perform a predetermined operation. Thesemechanisms operate symmetrically to each other so that the panel graspportion 15 is moved in a feed direction and upward/downward directionand panels 1 are sequentially transported to a next press station.

The panel grasp portion 15 comprises a work grasp portion 2 such as avacuum cup which sucks the panel (work 1), and a crossbar 3 to which thework grasp portion 2 is attached and which extends in a directionperpendicular to the transportation line. The link mechanisms 6 areconnected to both ends of the crossbar 3.

The slide mechanism 13 is constituted of a first slide mechanism 11 witha first slide block 4 and a second slide mechanism 12 with a secondslide block 5. The first slide mechanism 11 and the second slidemechanism 12 are attached to a V-shaped base member 16. Further, the twoslide mechanisms 11, 12 comprise direct acting actuators having the samelength. By driving these direct acting actuators, the first slide block4 and the second slide block 5 are linearly driven and can be accuratelypositioned by, for example, numerical control. 17 denotes a drive motorfor the direct acting actuator. In the present embodiment, the directacting actuator is a ball screw with a ball nut, but the presentinvention is not limited thereto, and the direct acting actuator may bea timing belt, a hydraulic cylinder, a rack and pinion, a linear motoror the like.

The first slide mechanism 11 is configured to linearly drive the firstslide block 4 in a direction inclined with respect to a horizontal planeso that the first slide block 4 is at a high position on thetransportation line upstream side and at a low position on thetransportation line downstream side within a driving region of the firstslide block 4. Moreover, the second slide mechanism 12 is configured tolinearly drive the second slide block 5 in a direction inclined withrespect to the horizontal plane so that the second slide block 5 is atthe low position on the transportation line upstream side and at a highposition on the downstream side within a driving region of the secondslide block 5. The second slide mechanism 12 is disposed closer to thetransportation line downstream side than the first slide mechanism 11,and is provided axially symmetrically to the first slide mechanism 11with respect to an axis Y vertical to the horizontal plane.

Lines of the two slide mechanisms 11, 12 extending downward in a slidedirection cross each other, and an angle θ formed therebetween is set at60°. It is to be noted that the formed angle θ is individuallydetermined for each press device by a space between the press stations14, 14, that is, by a transportation distance of the panel 1, and it isnot limited to the above-mentioned angle.

Furthermore, in the present embodiment, the first slide mechanism 11 andthe second slide mechanism 12 constitute a V-shaped slide mechanism inwhich their downward extension lines cross each other, but they are notlimited thereto. For example, the first slide mechanism 11 and thesecond slide mechanism 12 may constitute an inverted-V-shaped slidemechanism in which their upward extension lines cross each other, or mayconstitute an X-shaped slide mechanism in which the first slidemechanism 11 and the second slide mechanism 12 are displaced in thetransportation line width direction to cross their driving regions.

FIG. 4 is a schematic diagram of the panel transportation device 10 ofFIGS. 2 and 3. As shown in this drawing, the link mechanism 6 comprisesan output member 19 connected to both ends of the panel grasp portion 15(crossbar 3), and a first link 7 and a second link 8 pivotally connectedto the output member 19.

The first link 7 comprises two arms 7 a, 7 b having an equal length, andeach of the two arms 7 a, 7 b has one end pivotally connected to theoutput member 19 so as to be able to rotate around a horizontal axis(their pivotal connection points are indicated by a1, a2 from the left)and the other end pivotally connected to the first slide block 4 so asto be able to rotate around a horizontal axis (their pivotal connectionpoints are indicated by a3, a4 from the left). The second link 8comprises an arm having a length equal to that of the two arms 7 a, 7 bof the first link 7, and has one end pivotally connected to the outputmember 19 so as to be able to rotate around a horizontal axis (itspivotal connection point is indicated by b1.) and the other endpivotally connected to the second slide block 5 so as to be able torotate around a horizontal axis (its pivotal connection point isindicated by b2.). It is to be noted that in this drawing, the pivotalconnection point a2 and the pivotal connection point b1 are located onthe same axis, but they are not always need to be on the same axis.

A distance L1 between the pivotal connection points a1, a2 is set equalto a distance L2 between the pivotal connection points a3, a4. Accordingto this configuration, the two arms 7 a, 7 b are maintained in parallelwith each other, so that the output member 19 can always be held at apredetermined angle to the horizontal plane. That is, a parallel linka1, a2, a4, a3 is constructed, and even when a position of the outputmember 19 is changed, the output member 19 can be horizontallypositioned, and horizontally held without tilting the panel graspportion 15 (crossbar 3) attached to the output member 19.

FIGS. 5A to 5G are diagrams explaining a panel transportation operationof the panel transportation device according to the first embodiment ofthe present invention. In these drawings, P indicates a panel graspposition of the upstream press station, and Q indicates a panel mountingposition of the downstream press station.

FIG. 5A shows a position where the panel in the upstream press stationis grasped. From this position, the first slide block 4 and the secondslide block 5 are linearly driven obliquely and upwardly at apredetermined speed, thereby lifting the position of the output member19 to a position in FIG. 5B.

The first slide block 4 and the second slide block 5 are linearly drivenobliquely and upwardly at the predetermined speed from the position inFIG. 5B to move the entire link mechanism 6 in a panel transportationdirection while swiveling the link mechanism 6, thereby bringing theoutput member 19 attached to a tip of the link mechanism 6 to a positionin FIG. 5C. At this time, each of the slide blocks 4, 5 is controlled sothat the output member 19 substantially linearly moves in the paneltransportation direction from the position in FIG. 5B. Subsequently, thefirst slide block 4 is slightly obliquely and downwardly driven and thesecond slide block 5 obliquely and upwardly driven, so that the linkmechanism 6 further moves in the panel transportation direction whileswiveling, and the output member 19 moves to a point in the vicinity oflowermost points of the first slide mechanism 11 and the second slidemechanism 12 as shown in FIG. 5D.

Furthermore, the first slide block 4 is obliquely and downwardly drivenand the second slide block 5 is obliquely and upwardly driven, therebylinearly moving the output member 19 in the panel transportationdirection to bring it to a position in FIG. 5E. Then, the first slideblock 4 and the second slide block 5 are driven obliquely and downwardlyat the predetermined speed to bring them to positions in FIG. 5F, andthe slide blocks 4, 5 are further driven obliquely and downwardly fromthe positions in FIG. 5F, thus resulting in the panel mounting positionin FIG. 5G.

FIG. 6 is a diagram showing motion curves of the panel transportationdevice 10 of FIG. 2. As shown in this drawing, in accordance withoperations in FIGS. 5A to 5G, the material (panel) molded in theupstream press station is lifted by grasping it with the work graspportion (not shown) attached to the output member 19, and transported inthe feed direction, and then lowered in the downstream press station,thereby allowing the panel to be positioned at a mold position on amold. Subsequently, the output member is returned to a predeterminedstandby position while leaving the panel in the downstream pressstation, and molding is implemented in each press station.

According to the first embodiment of the present invention, by linearlydriving the first slide block 4 and the second slide block 5 at thepredetermined speed in predetermined directions, the link mechanism 6comprising the first link 7 and the second link 8 is swiveled, and thepanel grasp portion 15 attached to the output member 19 connected to thetip of the link mechanism 6 can be moved in the panel transportationdirection. Thus, movable portions can be reduced in size and weightwithout needing to provide the movable portions with drivers, andrigidity of the movable portions can be increased to restrain deflectionand vibration. Further, this panel transportation device can be providedfor each press station, and can have different motion for each pressstation.

It is to be noted that a case where the first link 7 constructs theparallel link has been described in the first embodiment, but this isnot a limitation. In an alternative embodiment, the second link 8 mayconstruct the parallel link to hold the panel grasp portion 15horizontal. Moreover, the parallel link does not need to be constructeddepending on a shape of the output member 19 and on how the crossbar 3is attached.

Next, a panel transportation device according to a second embodiment ofthe present invention will be described. FIG. 7 is a configurationdiagram of the panel transportation device according to the secondembodiment.

In the second embodiment, the first slide block 4 comprises twoindependent slide blocks 4 a, 4 b. Two arms 7 a, 7 b are pivotallyconnected to the output member 19 at one end, the other end of the arm 7a is pivotally connected to the slide block 4 a (left side in thedrawing), and the other end of the arm 7 b is pivotally connected to theslide block 4 b (right side in the drawing) so that they can rotatearound horizontal axis.

The first slide mechanism 11 is constituted of independent two slidemechanisms 11 a, 11 b which individually drive the two slide blocks 4 a,4 b. The two slide mechanisms 11 a, 11 b are configured by arranging theslide mechanisms similar to the first slide mechanism 11 in the firstembodiment in parallel so as to be displaced in a transportation linedirection and arranging them.

FIG. 8 is a schematic diagram of the panel transportation device of FIG.7. The two slide mechanisms 11 a, 11 b are disposed so that a distanceL2 between the pivotal connection points a3, a4 may be as long as thedistance L1 between the pivotal connection points a1, a2. The pivotalconnection points a1, a2, a4, a3 construct the parallel link.

FIGS. 9A to 9C are diagrams explaining a tilt operation of the paneltransportation device of FIG. 7. FIG. 9A shows a case in which the twoslide blocks 4 a, 4 b are driven at a position where the pivotalconnection points a3 and a4 hold the same height. FIG. 9B shows a casein which the two slide blocks 4 a, 4 b are driven at a position wherethe pivotal connection point a3 is lower than the pivotal connectionpoint a4, wherein relative positions of the pivotal connection pointsa3, a4 are changed to tilt the output member 19 via the two arms 7 a, 7b. FIG. 9C shows a case in which the two slide blocks 4 a, 4 b aredriven at a position where the pivotal connection point a3 is higherthan the pivotal connection point a4, wherein the output member istilted in a direction reverse to that in FIG. 9B. Thus, the first slideblock 4 is constituted of the two independent slide blocks 4 a, 4 b, andthe two slide blocks 4 a, 4 b are driven at different heights (atchanged relative positions) by the separate slide mechanisms 11 a, 11 bto tilt the output member 19, thereby allowing the panel grasp portion15 attached to the output member 19 to be tilted. Thus, the panel can begrasped/mounted at an optimum angle as required.

It is to be noted that the relative positions of the pivotal connectionpoints a3, a4 between the two slide blocks 4 a, 4 b and the two arms 7a, 7 b pivotally connected to the slide blocks 4 a, 4 b are generallycontrolled to be maintained in a state of FIG. 9A, so that the paneltransportation operation is substantially similar to that in the firstembodiment as simply shown in FIGS. 10A to 10C except when theabove-mentioned tilt operation is performed.

According to second embodiment of the present invention, the first slideblock 4 is constituted of the two independent slide blocks 4 a, 4 b, andthe two slide blocks 4 a, 4 b are driven at different heights (atchanged relative positions) by the separate slide mechanisms 11 a, 11 bto tilt the output member 19, thereby making it possible to obtain anadvantage, in addition to an advantage by the first embodiment, that thepanel grasp portion 15 attached to the output member 19 can be tilted.Thus, the panel can be grasped/mounted at an optimum angle as required.

It is to be noted that the first link 7 does not always need toconstruct the parallel link depending on the shape of the output member19 and on how the crossbar 3 is attached, as in the first embodiment.Further, the case has been described in a second embodiment wherein thefirst slide block 4 comprises two slides. Conversely, in an alternativeembodiment, it is also possible to have a configuration in which thesecond slide 5 comprises two slides, in which case configurations asshown in FIG. 8 may be built axially symmetrical with respect to theaxis Y.

Next, a panel transportation device according to the third embodiment ofthe present invention will be described. FIG. 11 is a configurationdiagram of the panel transportation device according to the thirdembodiment, and FIG. 12 is a schematic diagram thereof.

In the panel transportation device according to the first embodimentdescribed above, when the crossbar 3 is moved to a position in thevicinity of the panel mounting position Q as shown in a schematicdiagram of FIG. 13, the first slide block 4 is substantially as high asthe output member 19, and the two arms 7 a, 7 b might thus be brought inproximity to the extent that they overlap each other when viewed in thetransportation line width direction, or might overlap each other on thesame straight line. In this case, since the link mechanism approaches orcomes into the mechanical dead point, this could cause difficulty incontrolling the link mechanism. Moreover, the two arms cross each otherbeyond the mechanical dead point, with the result that the linkmechanism might become uncontrollable. In addition, when the second link8 is constituted of two arms contrary to the panel transportation deviceof FIG. 2, it is also assumed that a similar phenomenon occurs in thevicinity of the panel grasp position P.

Therefore, it is preferable to eliminate the mechanical dead point ofthe link mechanism and to improve controllability in any position of thepanel transportation operation.

Thus, in the panel transportation device according to the thirdembodiment of the present invention, a straight line passing the pivotalconnection points a1, a2 and a straight line passing the pivotalconnection points a3, a4 are inclined with respect to the horizontalplane, as shown in FIG. 12. An inclination angle α is set to an anglesuch that the two arms 7 a, 7 b can always hold a state in which they donot interfere with each other in a figure viewed from the paneltransportation direction. The “state in which they do not interfere witheach other” means a state in which the two arms 7 a, 7 b do not overlapeach other on one straight line or cross each other. In the presentembodiment, the angle α is set to 25 degrees, but it is not limited tothis angle, and the angle α is individually set in accordance with alength of the link mechanism 6. Thus, as shown in FIG. 14, even when theoutput member 19 is substantially as high as the first slide block 4 inthe vicinity of the panel mounting position, the first link alwaysconstructs a quadrilateral link. Therefore, since the mechanical deadpoint of the link mechanism 6 can be eliminated in any position of thepanel transportation operation, the controllability can be significantlyimproved.

The distance L1 between the pivotal connection points a1, a2 is as longas the distance L2 between the pivotal connection points a3, a4.According to this configuration, since the two arms 7 a, 7 b aremaintained in parallel, the output member 19 can always be held at apredetermined angle to the horizontal plane. On the other hand, thepanel grasp portion 15 is obliquely attached to the output member 19 soas to be able to horizontally grasp the panel 1. Thus, even when theparallel link a1, a2, a4, a3 is constructed and the position of theoutput member 19 is changed, the output member 19 can be horizontallypositioned, and horizontally held without tilting the panel graspportion 15 (crossbar 3) attached to the output member 19. In addition,configurations of other parts are similar to those in the firstembodiment. Moreover, the panel 15: transportation operation is alsosimilar to that in the first embodiment.

According to the third embodiment of the present invention, since thefirst link always constructs the quadrilateral link, the mechanical deadpoint of the link mechanism can be eliminated in any position of thepanel transportation operation. It is thus possible to obtain anadvantage that the controllability can be significantly improved.

It is to be noted that similar effects to those in the first embodimentcan naturally be obtained in the third embodiment.

Moreover, the case has been described in the third embodiment whereinthe first link 7 constructs the parallel link. However, this is not alimitation, and in an alternative embodiment, the second link 8 mayconstruct the parallel link to hold the panel grasp portion 15horizontal. Further, the parallel link does not always need to beconstructed depending on the shape of the output member 19 and on howthe crossbar 3 is attached, in which case one of the straight linepassing the pivotal connection points a1, a2 and the straight linepassing the pivotal connection points a3, a4 may be inclined withrespect to the horizontal plane at such an angle as to allow a state tobe held in which the two arms 7 a, 7 b do not interfere with each otherin the figure viewed from the panel transportation direction.

Next, a panel transportation device according to a fourth embodiment ofthe present invention will be described. FIG. 15 is a configurationdiagram of the panel transportation device according to the fourthembodiment, and FIG. 16 is a schematic diagram thereof.

In the second embodiment described above, when the crossbar 3 is movedto a position in the vicinity of the panel mounting position Q as shownin a schematic diagram of FIG. 17, the first slide block 4 is alsosubstantially as high as the output member 19, and the two arms 7 a, 7 bmight thus be brought in proximity to the extent that they overlap eachother when viewed in the transportation line width direction, or mightoverlap each other on the same straight line.

Therefore, in the fourth embodiment which is a preferred embodiment ofthe panel transportation device according to the second embodiment, thetwo slide mechanisms 11 a, 11 b control positions of the two slideblocks 4 a, 4 b so that the straight line passing the pivotal connectionpoints a1, a2 and the straight line passing the pivotal connectionpoints a3, a4 are inclined at a predetermined angle to the horizontalplane during normal transportation without the tilt operation, as shownin FIG. 16. At this time, the control is performed so that the two arms7 a, 7 b may form the angle α allowing a state in which they do notinterfere with each other in the figure viewed from the paneltransportation direction. Thus, as in the third embodiment, even whenthe output member 19 is in the vicinity of the panel grasp position, thefirst link always constructs the quadrilateral link. Therefore, sincethe mechanical dead point of the link mechanism 6 can be eliminated inany position of the panel transportation operation, the controllabilitycan be significantly improved. Configurations of other parts are similarto those in the second embodiment. Moreover, the panel transportationoperation is also similar to that in the second embodiment.

Furthermore, in an alternative embodiment, it is also possible to have aconfiguration in which the second slide 5 comprises two slides, in whichcase configurations as shown in FIG. 15 may be built axiallysymmetrically with respect to the axis Y.

Next, a panel transportation device according to a fifth embodiment ofthe present invention will be described. FIG. 18 is a configurationdiagram of the panel transportation device according to the fifthembodiment.

In the panel transportation device according to the second and fourthembodiments described above, a tilt mechanism to tilt the panel graspportion 15 constructs part of the link mechanism 6. Therefore, inconstructing the link mechanism 6, there are needed components similarto structural components to position the panel grasp portion 15, such asthe slide block, the slide mechanism and the arm. Thus, a structure ofthe entire device becomes complicated.

Furthermore, in the panel transportation device according to the firstand second embodiments, the link mechanism approaches or comes into themechanical dead point, so that the link mechanism might becomeuncontrollable, as described with FIG. 13 and FIG. 17.

Therefore, it is preferable that the entire device can be simplifiedeven when it comprises the tilt mechanism, and that the mechanical deadpoint of the link mechanism can be eliminated in any position of thepanel transportation operation to improve the controllability.

Thus, the panel transportation device according to the fifth embodimentfurther comprises a tilt mechanism 18 in addition to the panel graspportion 15, the link mechanism 6 and the slide mechanism 13, as shown inFIG. 19.

The panel grasp portion 15 and the slide mechanism 13 are similar tothose in the panel transportation device according to the first tofourth embodiments.

FIG. 19 is a schematic diagram of the panel transportation device 10 ofFIG. 18. As shown in this drawing, the link mechanism 6 comprises theoutput member 19 connected to both ends of the panel grasp portion 15(crossbar 3), and the first link 7 and the second link 8 pivotallyconnected to the output member 19.

The first link 7 has one end pivotally connected to the output member 19so as to be able to rotate around the horizontal axis (its pivotalconnection point is indicated by a1.) and the other end pivotallyconnected to the first slide block 4 so as to be able to rotate aroundthe horizontal axis (its pivotal connection point is indicated by a2.).The second link 8 comprises an arm having a length equal to that of thefirst link 7, and has one end pivotally connected to the output member19 so as to be able to rotate around the horizontal axis (its pivotalconnection point is indicated by b1.) and the other end pivotallyconnected to the second slide block 5 so as to be able to rotate aroundthe horizontal axis (its pivotal connection point is indicated by b2.).It is to be noted that in this drawing, the pivotal connection point a1and the pivotal connection point b1 are located on the same axis, butthey are not always needed to be on the same axis.

The tilt mechanism 18 comprises a rotary actuator 21 installed in thefirst slide block 4, a first arm 22, a second arm 23 and a coupling rod24. One end of the first arm 22 is fixed to a drive shaft of the rotaryactuator 21, and one end of the second arm 23 is fixed to the outputmember 19. The coupling rod 24 couples the first arm 22 with the secondarm 23, and has one end pivotally connected to the other end of thefirst arm 22 so as to be able to rotate around a horizontal axis (itspivotal connection point is indicated by c2.) and the other endpivotally connected to the other end of the second arm 23 so as to beable to rotate around a horizontal axis (its pivotal connection point isindicated by c1.). According to this configuration, the rotary actuator21 is driven, and the rotary driving of this rotary actuator 21 istransmitted via the first arm 22, the coupling rod 24 and the second arm23, thereby tilting the panel grasp portion 15. In addition, the tiltmechanisms 18 are provided symmetrically to each other on both sides ofthe panel grasp portion 15 in the panel transportation device 10 shownin FIG. 18, but the tilt mechanism 18 may be provided on one side alone.Moreover, in the present embodiment, the first arm 22, the second arm 23and the coupling rod 24 constitute a transmission mechanism in thepresent invention.

The distance L1 between the pivotal connection points c1, a1 is as longas the distance L2 between the pivotal connection points c2, a2, and thecoupling rod 24 and the first link 7 have an equal length. Thus, aparallelogram sequentially passing the pivotal connection points c1, c2,a2, a1 is constructed, and the rotary actuator 21 is installed in andfixed to the first slide block 4 by this construction, so that the panelgrasp portion 15 can be always held in a constant posture withoutdriving the rotary actuator 21 during the normal transportation withoutthe tilt operation. That is, if the panel grasp portion 15 is positionedto be horizontal, the panel grasp portion 15 (crossbar 3) can be heldhorizontal without driving the rotary actuator 21 even when the positionof the output member 19 is changed.

FIGS. 20A to 20G are diagrams explaining the panel transportationoperation of the panel transportation device according to the fifthembodiment of the present invention. In these drawings, P indicates thepanel grasp position of the upstream press station, and Q indicates thepanel mounting position on the downstream side.

FIG. 20A shows a position where the panel in the upstream press stationis grasped. From this position, the first slide block 4 and the secondslide block 5 are linearly driven obliquely and upwardly at apredetermined speed, thereby lifting the position of the output member19 to a position in FIG. 20B.

The first slide block 4 and the second slide block 5 are linearly drivenobliquely and upwardly at the predetermined speed from the position inFIG. 20B to move the entire link mechanism 6 in the panel transportationdirection while swiveling the link mechanism 6, thereby bringing theoutput member 19 attached to the tip of the link mechanism 6 to aposition in FIG. 20C. At this time, each of the slide blocks 4, 5 iscontrolled so that the output member 19 substantially linearly moves inthe panel transportation direction from the position in FIG. 20B.Subsequently, the first slide block 4 is slightly obliquely anddownwardly driven and the second slide block 5 obliquely and upwardlydriven, so that the link mechanism 6 further moves in the paneltransportation direction while swiveling, and the output member 19 movesto a position in the vicinity of the lowermost points of the first slidemechanism 11 and the second slide mechanism 12 as shown in FIG. 20D.

Furthermore, the first slide block 4 is obliquely and downwardly drivenand the second slide block 5 is obliquely and upwardly driven, therebylinearly moving the output member 19 in the panel transportationdirection to bring it to a position in FIG. 20E. Then, the first slideblock 4 and the second slide block 5 are driven obliquely and downwardlyat the predetermined speed to bring them to positions in FIG. 20F, andthe slide blocks 4, 5 are further driven obliquely and downwardly fromthe positions in FIG. 20F, thus resulting in the panel mounting positionin FIG. 20G.

FIGS. 21A to 21C are diagrams explaining the tilt operation of the paneltransportation device according to the fifth embodiment. Among thesedrawings, FIG. 21A shows a normal position when the tilt operation isnot performed. When the panel grasp portion 15 is to be tilted, therotary actuator 21 is driven in an arrow direction in the drawings,thereby operating the rotary actuator 21 as in FIG. 21B. On the otherhand, when the panel grasp portion 15 is to be tilted in a directionopposite to that in FIG. 21B, the rotary actuator 21 is driven in adirection reverse to that in FIG. 21B, thereby operating the rotaryactuator 21 as in FIG. 21C. Thus, the panel can be grasped/mounted at anoptimum angle as required.

According to the fifth embodiment of the present invention, the tiltmechanism 18 is constituted of the rotary actuator 21 installed in thefirst slide block 4 and of the transmission mechanism (the first arm 22,the second arm 23 and the coupling rod 24), and the tilt mechanism cantherefore be configured in a structure simpler than those in the thirdand fourth embodiments.

Furthermore, since the tilt mechanism 18 and the link mechanism 6 areseparately configured, the mechanical dead point of the link mechanism 6can be eliminated. Thus, the controllability is significantly improved.

It is to be noted that in the fifth embodiment, the rotary actuator 21of the tilt mechanism 18 is installed in the first slide block 4, butthe rotary actuator 21 may be installed in the second slide block 5instead, and the panel grasp portion may be tilted by the first arm 22,the second arm 23 and the coupling rod 24 in the same manner. Moreover,the second arm 23 of the tilt mechanism 18 is fixed to the output member19, but it may also be directly fixed to the panel grasp portion 15(crossbar 3) to tilt the panel grasp portion 15 instead. Further, thesecond arm 23 may be a member integrally formed with the output member19 or the panel grasp portion. Still further, a quadrangle sequentiallypassing the pivotal connection points c1, c2, a2, a1 does not alwaysconstruct a parallelogram depending on the shape of the output member 19and on how the crossbar 3 is attached.

Next, a panel transportation device according to a sixth embodiment ofthe present invention will be described. FIG. 22 is a configurationdiagram of the panel transportation device according to the sixthembodiment. In the sixth embodiment, the tilt mechanism of the paneltransportation device according to the fifth embodiment has anotherconfiguration.

As shown in FIG. 22, in the sixth embodiment, the tilt mechanism 18comprises the rotary actuator 21 installed in the first slide block 4, afirst pulley 26 fixed to the drive shaft of the rotary actuator, asecond pulley 27 fixed to the output member 19, and a drive belt 28which transmits rotary driving of the first pulley 26 to the secondpulley 27. A ratio of nominal diameter of the first pulley 26 to that ofthe second pulley 27 is 1 to 1. In the present embodiment, the firstpulley 26, the second pulley 27 and the drive belt 28 constitute thetransmission mechanism of the present invention. That is, in the presentembodiment, a belt drive mechanism is employed as the transmissionmechanism of the tilt mechanism 18. According to this configuration, therotary actuator 21 is driven, and the rotary driving of this rotaryactuator 21 is transmitted via the first pulley 26, the drive belt 28and the second pulley 27, thereby tilting the panel grasp portion 15.Configurations of other parts are similar to those in the fifthembodiment.

FIG. 23 simply shows the panel transportation operation of the paneltransportation device according to the sixth embodiment of the presentinvention. FIG. 23 shows the panel transportation operation during thenormal transportation without the tilt operation. As shown therein,function of the belt drive mechanism allows the panel grasp portion 15to be always held in a constant posture in any position without drivingthe rotary actuator 21. That is, the ratio of the nominal diameter ofthe first pulley 26 to that of the second pulley 27 is 1 to 1, so thateven if the position of the output member 19 is changed, the secondpulley 27 does not rotate relative to the horizontal plane unless thefirst pulley 26 rotates. As a result, the output member 19 is also heldat a constant angle to the horizontal plane.

In the panel transportation device 10 according to the presentembodiment, when the tilt operation is performed, the rotary actuator 21may be driven in the same direction as a direction in which the panelgrasp portion 15 is desired to be tilted. It is to be noted that thepanel transportation operation of the panel transportation deviceaccording to the sixth embodiment is substantially similar to that inthe fifth embodiment, and therefore will not be described.

Similar effects to those in the fifth embodiment can be obtainedaccording to the sixth embodiment of the present invention.

It is to be noted that the rotary actuator 21 of the tilt mechanism 18has been installed in the first slide block 4, but the rotary actuator21 may be installed in the second slide block 5 instead, and the panelgrasp portion 15 may be tilted by the first pulley 26, the second pulley27 and the drive belt 28 in the same manner. Moreover, the second pulley27 is fixed to the output member 19, but it may also be directly fixedto the panel grasp portion 15 (crossbar 3) to tilt the panel graspportion 15 instead. Further, the second pulley 27 may be a memberintegrally formed with the output member 19 or the panel grasp portion.

It is to be noted that several preferred embodiments of the paneltransportation device of the present invention have been described, butit will be understood that the scope of protection covered by thepresent invention is not limited to these embodiments. Conversely, thescope of protection of the present invention covers all improvements,modifications and equivalents included in the accompanying claims.

1. A panel transportation device comprising: (a) a panel grasp portionfor grasping a panel; (b) a link mechanism for moving the panel graspportion in a panel transportation direction; and (c) a slide mechanismfor operating the link mechanism so as to move the panel grasp portionin the panel transportation direction and moving the entire linkmechanism, wherein the slide mechanism is constituted of a first slidemechanism and a second slide mechanism provided closer to atransportation line downstream side than the first slide mechanism; thefirst slide mechanism has a first slide block connected to the linkmechanism, and is configured to linearly drive the first slide block,the second slide mechanism has a second slide block connected to thelink mechanism, and is configured to linearly drive the second slideblock, a move direction of the first slide block inclines relative to amove direction of the second slide block, and the link mechanismcomprises i. an output member connected to the panel grasp portion; ii.a first link whose one end is pivotally connected to the output memberand whose other end is pivotally connected to the first slide block; andiii. a second link whose one end is pivotally connected to the outputmember and whose other end is pivotally connected to the second slideblock; wherein the link mechanism is constructed such that the panelgrasp portion is moved in the panel transportation direction byindividually and linearly driving the first slide block and the secondslide block.
 2. The panel transportation device according to claim 1,characterized in that a pair of link mechanisms and a pair of slidemechanisms are provided symmetrically to each other on both sides of thepanel grasp portion.
 3. The panel transportation device according toclaim 1, characterized in that the first slide block is linearly drivenin a direction inclined with respect to a horizontal plane so that thefirst slide block is at a high position on a transportation lineupstream side and at a low position on the transportation linedownstream side within a driving region of the first slide block; andthe second slide block is linearly driven in a direction inclined withrespect to the horizontal plane so that the second slide block is at alow position on the transportation line upstream side and at a highposition on the transportation line downstream side within a drivingregion of the second slide block.
 4. The panel transportation deviceaccording to claim 1, characterized in that the first link comprises twoarms, and each of the two arms has one end pivotally connected to theoutput member and the other end pivotally connected to the first slideblock.
 5. The panel transportation device according to claim 4,characterized in that the first slide block is constituted of two slideblocks; the first slide mechanism comprises two driving means forindividually driving the two slide blocks; the other ends of the twoarms are pivotally connected to the two slide blocks; and relativepositions of the two slide blocks are changed to tilt the panel graspportion connected to the output member.
 6. The panel transportationdevice according to claim 4, characterized in that a straight linepassing pivotal connection points of the two arms and the first slideblock, or a straight line passing pivotal connection points of the twoarms and the output member, is inclined with respect to the horizontalplane so as to always hold a state where the two arms do not interferewith each other in a plane viewed from a transportation line widthdirection, or characterized in that the straight line passing pivotalconnection points of the two arms and the first slide block and thestraight line passing pivotal connection points of the two arms and theoutput member are inclined with respect to the horizontal plane so as toalways hold a state where the two arms do not interfere with each otherin the plane viewed from the transportation line width direction.
 7. Thepanel transportation device according to claim 5, characterized in thata straight line passing pivotal connection points of the two arms andthe first slide block, or a straight line passing pivotal connectionpoints of the two arms and the output member, is inclined with respectto the horizontal plane so as to always hold a state where the two armsdo not interfere with each other in a plane viewed from a transportationline width direction, or characterized in that the straight line passingpivotal connection points of the two arms and the first slide block andthe straight line passing pivotal connection points of the two arms andthe output member are inclined with respect to the horizontal plane soas to always hold a state where the two arms do not interfere with eachother in the plane viewed from the transportation line width direction.8. The panel transportation device according to claim 1, characterizedin that the second link comprises two arms, and each of the two arms hasone end pivotally connected to the output member and the other endpivotally connected to the second slide block.
 9. The paneltransportation device according to claim 8, characterized in that thesecond slide block is constituted of two slide blocks; the second slidemechanism comprises two driving means for individually driving the twoslide blocks; the other ends of the two arms are pivotally connected tothe two slide blocks; and relative positions of the two slide blocks arechanged to tilt the panel grasp portion connected to the output member.10. The panel transportation device according to claim 8, characterizedin that a straight line passing pivotal connection points of the twoarms and the second slide block, or a straight line passing pivotalconnection points of the two arms and the output member, is inclinedwith respect to the horizontal plane so as to always hold a state wherethe two arms do not interfere with each other in a plane viewed from atransportation line width direction, or characterized in that thestraight line passing pivotal connection points of the two arms and thesecond slide block and the straight line passing pivotal connectionpoints of the two arms and the output member are inclined with respectto the horizontal plane so as to always hold a state where the two armsdo not interfere with each other in the plane viewed from thetransportation line width direction.
 11. The panel transportation deviceaccording to claim 3, further comprising (d) a tilt mechanism fortilting the panel grasp portion, characterized in that the tiltmechanism comprises i. a rotary actuator installed in the first slideblock or the second slide block; and ii. a transmission mechanism fortransmitting rotary driving of the rotary actuator to tilt the panelgrasp portion.
 12. The panel transportation device according to claim11, characterized in that the transmission mechanism comprises a firstpulley fixed to the drive shaft of the rotary actuator, a second pulleyfixed to or integrally formed in the output member or the panel graspportion, and a drive belt for transmitting rotary driving of the firstpulley to the second pulley.
 13. The panel transportation deviceaccording to claim 3, characterized in that the first slide mechanismand the second slide mechanism comprise direct acting actuators whichlinearly drive the first slide block and the second slide block.
 14. Thepanel transportation device according to claim 13, characterized in thatthe direct acting actuator is a ball screw with a ball nut, a timingbelt, a hydraulic cylinder, a rack and pinion, or a linear motor. 15.The panel transportation device according to claim 14, characterized inthat the panel grasp portion comprises a crossbar connected to the linkmechanism, and a work grasp portion attached to the crossbar.
 16. Thepanel transportation device according to claim 1, wherein the linkmechanism is constructed such that the first slide block and the secondslide block are connected to the panel grasp portion.
 17. A paneltransportation device comprising: (a) a panel grasp portion for graspinga panel; (b) a link mechanism for moving the panel grasp portion in apanel transportation direction; and (c) a slide mechanism for operatingthe link mechanism so as to move the panel grasp portion in the paneltransportation direction and moving the entire link mechanism, whereinthe slide mechanism is constituted of a first slide mechanism and asecond slide mechanism provided closer to a transportation linedownstream side than the first slide mechanism; the first slidemechanism has a first slide block connected to the link mechanism, andis configured to linearly drive the first slide block, the second slidemechanism has a second slide block connected to the link mechanism, andis configured to linearly drive the second slide block, wherein thesecond slide block is constituted of two slide blocks and the secondslide mechanism comprises two driving means for individually driving thetwo slide blocks, a move direction of the first slide block inclinesrelative to a move direction of the second slide block, and the linkmechanism comprises i. an output member connected to the panel graspportion; ii. a first link whose one end is pivotally connected to theoutput member and whose other end is pivotally connected to the firstslide block; and iii. a second link whose one end is pivotally connectedto the output member and whose other end is pivotally connected to thesecond slide block, wherein the second link comprises two arms, and eachof the two arms has one end pivotally connected to the output member andthe other end pivotally connected to the second slide block; wherein thelink mechanism is constructed such that the panel grasp portion is movedin the panel transportation direction by individually and linearlydriving the first slide block and the second slide block, and the otherends of the two arms are pivotally connected to the two slide blocks ofthe second slide block, and relative positions of the two slide blocksare changed to tilt the panel grasp portion connected to the outputmember, and wherein a straight line passing pivotal connection points ofthe two arms and the second slide block, or a straight line passingpivotal connection points of the two arms and the output member, isinclined with respect to the horizontal plane so as to always hold astate where the two arms do not interfere with each other in a planeviewed from a transportation line width direction, or wherein thestraight line passing pivotal connection points of the two arms and thesecond slide block and the straight line passing pivotal connectionpoints of the two arms and the output member are inclined with respectto the horizontal plane so as to always hold a state where the two armsdo not interfere with each other in the plane viewed from thetransportation line width direction.
 18. A panel transportation devicecomprising: (a) a panel grasp portion for grasping a panel; (b) a linkmechanism for moving the panel grasp portion in a panel transportationdirection; (c) a slide mechanism for operating the link mechanism so asto move the panel grasp portion in the panel transportation directionand moving the entire link mechanism; and (d) a tilt mechanism fortilting the panel grasp portion, wherein the tilt mechanism comprises i.a rotary actuator installed in a first slide block or a second slideblock; and ii. a transmission mechanism for transmitting rotary drivingof the rotary actuator to tilt the panel grasp portion, wherein thetransmission mechanism comprises a first arm whose one end is fixed to adrive shaft of the rotary actuator, a second arm whose one end is fixedto or integrally formed in an output member or the panel grasp portion,and a coupling rod whose one end is pivotally connected to the other endof the first arm and whose other end is pivotally connected to the otherend of the second arm and which couples the first arm with the secondarm; wherein the slide mechanism is constituted of a first slidemechanism and a second slide mechanism provided closer to atransportation line downstream side than the first slide mechanism; thefirst slide mechanism has the first slide block connected to the linkmechanism, and is configured to linearly drive the first slide block,the second slide mechanism has the second slide block connected to thelink mechanism, and is configured to linearly drive the second slideblock, a move direction of the first slide block inclines relative to amove direction of the second slide block, and the link mechanismcomprises i. the output member connected to the panel grasp portion; ii.a first link whose one end is pivotally connected to the output memberand whose other end is pivotally connected to the first slide block; andiii. a second link whose one end is pivotally connected to the outputmember and whose other end is pivotally connected to the second slideblock; wherein the link mechanism is constructed such that the panelgrasp portion is moved in the panel transportation direction byindividually and linearly driving the first slide block and the secondslide block, and wherein the first slide block is linearly driven in adirection inclined with respect to a horizontal plane so that the firstslide block is at a high position on a transportation line upstream sideand at a low position on the transportation line downstream side withina driving region of the first slide block; and the second slide block islinearly driven in a direction inclined with respect to the horizontalplane so that the second slide block is at a low position on thetransportation line upstream side and at a high position on thetransportation line downstream side within a driving region of thesecond slide block.